Radon gas is a significant health hazard that has only relatively recently been recognized as causing up to 20,000 deaths each year in the United States alone. The United States Environmental Protection Agency has estimated that one million to five million homes may have unhealthful radon levels. In non-inhabited areas, radon gas naturally diffuses through the soil into the atmosphere where it is harmlessly dispersed. Wherever there is a house, however, the radon gas leaks into subterranean rooms around the foundation slab and through cracks in the foundation or subterranean walls, and diffuses through porous cement and concrete blocks. And, since radon is heavier than air, the subterranean room acts as a collector of radon gas, holding and concentrating the gas to lethal levels.
The Environmental Protection Agency has published A HOMEOWNER'S GUIDE, August, 1986, OPA-86-005, and a TECHNICAL GUIDANCE Manual, EPA/625/5-86/019, that outline methods for reducing radon gas concentrations inside subterranean rooms of houses. These pamphlets discuss the method of using a drainage tile system located outside the house to collect and discharge radon gas and water, but this system is very expensive and there is no disclosure of how the system may be used inside the house. The pamphlets also discuss an inside baseboard system to collect and exhaust radon gas, but there is no disclosure that the baseboard system can collect and discharge both radon gas and fluids. It is also the experience of those individuals in the field that existing baseboard systems that collect and vent radon gas cannot also collect and discharge fluids, due in part to the pressures exerted by the fluid on the collection system. There is no suggestion in the literature that any inside collecting and venting apparatus has been or could be used to collect and drain both fluids and radon gas.
The leakage of water into subterranean rooms results in destructive damage to furniture, wall coverings, structural supports, upholstery, equipment, and other items. A moist or wet room may also result in health problems that can cause a room to be uninhabitable. Even rooms that are normally dry and comfortable may be flooded after especially wet conditions like a heavy rainfall.
U.S. Pat. No. 3,344,569 to Cotten discloses a basement drain conduit that overlies the basement floor and wall. It is designed to drain water that seeps into a basement, but it is not an airtight system. Indeed, the Cotten patent touts as one of its major advantages access to the interior of the conduit so that sediment may be removed. This results in an unsealed and open system. Cotten also provides multiple open drains or open sumps to collect and dispose of excess water. Because the drain system is not sealed, any dangerous gases will escape from the collection system and, moreover, exacerbate the problem of admitting lethal radon gas into the room. There is no suggestion that the system will work to discharge gases, nor is there a disclosure that the system can be or was intended to be used to discharge both radon gas and fluids.